A Building's Vapour Barriers Don't Work the Way You Think!

Click
on the image to download a print quality scan

Vapour barriers are crucial in buildings – but they don't work the way you would expect. Plastics, for example, are virtually always good at keeping out liquid water – but some of them, including silicone mastics, and PVOH are so poor at keeping water vapour out that they almost might as well not be there at all. All building products, coatings and systems work differently for water as a vapour and as a liquid, so they need to be tested for vapour permeability.

Traditionally this has been a very slow and expensive process, but now the latest Versaperm VI system for building materials makes it faster, cheaper and more accurate. As another plus you can simulate the diurnal cycle and measure it across winter's freezing sub-zero temperatures and summer's most blazing days.

The system can measure the permeability (and dew point) for anything from a single vapour barrier through to entire structures – as well as building boards, adhesives, mastics, walls, screeds, windows, laminates and roofing felts.

Results are typically accurate in the parts per million range and the equipment can optionally measure it not just for water vapour but also for CO2, hydrocarbons, oxygen and virtually any other gas or vapour needed.

Versaperm is a world-technology leader and offers not just equipment but also a fast turn-around building products lab testing service. Results from our testing service are typically produced within 24 hours.